Pressure-gage.



C. J. MANNING.

PRESSURE GAGE.

APPLICATION FILED MAY 17, 1910.

1,043,61 8.- Patnted Nov. 5, 1912.

UNTTED STATES PATENT OFFHJE.

COLEMAN J. MANNING, F MEDFORD, MASSACHUSETTS, ASSIGNOR T0 AMERICAN QT AM GAUGE AND VALVE MANUFACTURING COMPANY. OF BOSTON, MASSACHU- SETTS, A CORPORATION OF NE'VV JERSEY.

PRESSURE-GAGE Specification of Letters Patent.

Patented Nov. 5. 1912.

Application filed May 17, 1910. Serial No. 561,905.

To all 11.7mm it may concern:

Be it known that l. COLEUAN J. H smrvc, of Medford, in the county of Middlesex and State of Ma sachusetts, have invented certain new and useful Improvements in Pressure-Gages, of which the following is a specification.

.iny invention,

This invention relates to gages for indicating fluid pressures of thety 'ie in which a Bourdon tube spring is used, and has for its object to provide an imprm'cd means by which the position of the pointer or other indicating element may be adjusted more easily and accurately than heretofore, and particularly without-rerpiiring removal ot the dial from the case of the gage.

Another-object is to improve the construction of the gage to permit more ready and easy mounting of the tube spring and the head or socket of the gage in the case.

The manner in which my invention carried into effect is described in detail in the following speciti :ation,- and illustrated in the accom 'ianying drawings, in which,

Figurel represents a gage ha ring my in vcntion applied thereto shown in front, elevation. l ig. E is an elevation of the gage with the dial removed, showing the elen'ients in the form in-which at present l. prefer to embody my invention. Fig. 3 is a detail elevation oi the construction by which the first of the abovenamed objects is secured. Fig.4 represents in elevation the two mem- -bers or elements shown in Fig. 3 separated from one,another. Fig. 5 is a perspective \"icw of the lower part of the gage casing illustrating the other principal feature of Fig. 6 is a perspective view of the head inf-socket to which the tube spring is conznacted, and into which the fluid is admitted for actuating the gage.

The same reference characters indicate the same parts in all the figures.

lteterring "to the drawings, Fig. l, the casing of thegage is designated by the numei al lat'ron'i which at the bottom projects a nipple 2, with which the pipe conductihg the steam or other fluid of which the pri ssure is to be measured is connected. 'lhe'usual graduated dial is "eprcsented at and the pointer cotiperating with the dial for indicating pressures is represented at 4. This hohlcr secured upon the end of a pin or arbor 5, which passes through. an

and first to- .distorted by the fluid pressure, the segment 11 oscillated by secured upon the spindle or arbor 7 of the pointer. The lever 10 is pivoted upon a stud l3, and is connected \\'ltll the arm 3 through the link 9. tube is forced into it. under Thus when the means of the linkage described and pointer thereby moved rotarily spindle 5 and. pinion12, which meshes with the segment. The usual hair spring 14 is connected to the spindle 5 and to a fixed stud 15.

lt trerpiei'itly happens that the pointer fails to occupy exactly the zero position when pressure is removed from the tube, owing to incorrect adjustment ot the motion-transmitting conne tions, and for the purpose of correcting the pointer l have devised a means by which the angular rela tion of the arm 8 with l'tSjitvl to the tube may be adjusted to the amount necessary for the required correction, and thus without necessitating removal of the diai'. For the purpose of permitting such adjustment of the arm the spring tube is provided with the projecting finger 16, to which the arm 8' is piw ta Hy connected by means of av screw 17. In the end of the arm is a transuersc the slot; 18 which is curved, its center of curva ture being the aperture 19 through which the screw 17 passes. A second screw 20 passes through theslot 18 and is thr aded into a tapped hole 21 in the finger 16. By loosening the screw 20 the arm 8 may be adjusted angularly about the pivot screw 17 until the pointer occupies the desired position, whereupon the screw 20' may be tightened to hind the armiin this adjustment. The head of the screw 20 overlaps the sides of the slot- 18 and so binds the arm 8 in fixed relation to the tube.

In the dial is an aperture 22 d irect'h over the screw 20 for the purpose of ad through the 'so far as I am aware, it is necessary to re- .my invention it is only necessary after looscircular portion 24,

mitting a screw-driver to engage and loosen the screw whenever adjustment of the pointer l is required without necessitating removal of the dial. As will be readily understood, when this screw is loosened, the pointer may be moved in either direction to the desired point, and the screw may be again tightened, whereupon the adjustment of the pointer will be preserved. Preferably the head of the screw 20 is comparatively long, so that it lies but a short distance back of the dial and thus is readily accessible.

I am aware that heretofore gages have been designed in which adjustment. of the linkage between the spring tube and the pointer is possible, but in all of such gages,

provide shelves 27, on which shouldersQS of the head 7 rest, which shelves, the noncircular shank of the head and the screws in the lug 25 cooperating with the shelves 27, the walls ol the slot 23 and the back wall 'of the case respectively, securely hold the head? and the sprijhg tube in place with the latter in its proper relation to the back of the case. This rotation-preventing connection between the head and the case enables force to be applied to the latter for turning it, without injuring the Bourdon tube. It is sometimes necessary or desirablc to turn the gage somewhat after it has been set up, and the easiest and most apparent way to do so is by grasping the gage case and giving it a twist. As the nipple is screwed tightly into the pipe which conducts the pressureiiuid to the gage, there is, of course, considerable resistance to turning, and in. the old type of gage this resistance is borne entirely by the screws which secure the head to the back of, the case. The result is that the screws are more or less distorted and the case sometimes turned relatively. to the head and. Bourdon tube by a great enough amount to interfere with the perfect operation of the tube. Op-

move the dial before any such adjustment can be accomplished. Moreover to the best of my knowledge there is no other form of adjustable linkage which can be adjusted so easily and accurately as this one, for with ening the clamp screw to shift the pointer into the desired location, and the adjustment is made. In the other adjustable devices, the adjustment is made by relative movement of parts remote from the pointer at such points that the movement of the pointer in response to such adjustment furnishes no guide to the accuracy of the adjustment.

The other principal object of my invention relates to the manner of assembling the Bourdon spring in the case. Hereto'l'ore it has been the usual practice to pass the nippie 2 through a circular hole in the side of the case from he interior thereof, and secure the heat 7 in the case by screws. Such a mode of assembling is attended with (lifticulties, in that it involves a more or less serious distortion of the spring tube, before it and the nipple can be put in the case prior topassing the nipple through the aperture in the side of the case. In order to make the insertion of the spring tube more simple, I form a slot 23 in the circular wall of the casing extending in from the edge thereof, into which the head 7 is passed. This head is provided with a nonpreferably rectangular in outline, the opposite sides of which fit the sides of the slot 23. On the head is alug 25 which bears against the back wall 26 of the casing and is provided with one or more apertures through which screws are passed to secure it in the casing. i this connection it should be noted that'the gage case as usually constructed consists of a flat back wall from which projects a circular flange forming the side walls of the case, the front being open until covered by the removable dial 3. Then by forming an open slot 23 in the curved wal l. of the case, a passage is made into which the gage head may be very easily passed. At each side of the been the cause of inaccurate working or pressure gages and unmerited blame of the manufacturers thereof. lVith the construction which I have invented, that of a, nonrotative connection between the head and the case, possibility of any such disarrangement is absolutely prevented, no matter how great the force employed in twisting the case, or how great the resistance of the nipple may be to turning. In other words the case of the gage itself may be used as a wrench in applying the gage to a pressure pipe or in adjusting it thereon, and when so used there will be. no disarrangement of the working part I claim,-

1. In a pressure gage a dial having an aperture, an indicating pointer movable over said dial, a pressure-actuated member, connections between said member and pointer, whereby movement of the 'former is transmitted to the latter, said connections being adjustable for correcting the position of the pointer, and a clamp for securing the adjustment of such connections accessible through such aperture.

2.. In a pressure gage the combination of Bourdon tube, a pointer, an oscillating lever in geared. relation with said pointer, an arm pivotany mounted upon said Bourdon tube, a link connecting said arm and lover, and means for securing said arm to said tube in any angular. adjustment with respectthereto within limits.

' 3. In a pressure gage a Bourdon tube, a

erat-ions of this character have frequently slot the walls of the case are thickened to die extentfing; over said tube and having I said arm to retain the latter an aperture a pomter movable over said (1121, metioh-transmitting connectione between said tube and pointer also covered by said diel, end means fer permitting adjust ment of said eennections to shift the position of the pointer Without ehsering iis emphrtude 0f swing, accessible through the eperture in said die]. K I; In a pressure gage e. curved spring wee, en erm plvoted to sand tube and hevin a transverse slot, a clamp member passthrough said slot into engagement with said tube and adapted to be clamped against in any angular position Within limits With respect to said tube, a pointer, and motion-transmitting connection between said am and pointex: ineluding a segment geared to the polnter and a link pivoted he said segment and the arm whereby the pointer is oscillated in response to distortions of the tube.

In" testimony signature, in presence of two Witnesses.

COLEMAN J. MANNING. Witnesses:

:HARRY L. ALLEN, 1 W. PEZZETTI.

whereof I have aflixed my 

